How can you use dynamic analysis to design structures for extreme events?

2 Why use dynamic analysis?

Dynamic analysis is essential for designing structures for extreme events, as it can take into account the intensity and duration of the dynamic loads, the dynamic characteristics of the structure, its nonlinear behavior, and the interaction between structural elements. These aspects can vary significantly depending on the type and location of the event, and can influence the structure's response to dynamic loads, reduce its stiffness and strength, increase its deformation and energy dissipation, and affect its global and local behavior.

3 How to perform dynamic analysis?

To perform dynamic analysis, you need to define the structural model, including the geometry, material properties, boundary conditions, and load cases. Then, choose the type of dynamic analysis method that suits your design objectives and available data. Modal analysis can be used to identify natural frequencies and modes of the structure, response spectrum analysis can estimate the maximum response of the structure under seismic loads, time history analysis can simulate the detailed response of the structure under specific load histories, and random vibration analysis can analyze the response of the structure under stochastic loads. Apply dynamic loads and run the analysis using a software tool such as ANSYS, SAP2000, ETABS, or ABAQUS. Afterwards, interpret the results and evaluate the performance of the structure under dynamic loads by assessing displacements, stresses, strains, forces, moments, or energy of the structure against design criteria or codes.

4 What are the advantages of dynamic analysis?

Dynamic analysis has several advantages for designing structures for extreme events, such as providing more accurate and realistic results than static analysis. It can also help to optimize the structural design by identifying the critical load cases, modes, and elements that affect the dynamic response of the structure. Additionally, dynamic analysis can improve the structural safety and resilience by evaluating the nonlinear behavior, damage, and failure modes of the structure under dynamic loads. Furthermore, it can enhance the structural functionality and serviceability by assessing the dynamic effects on the occupants, equipment, or utilities of the structure.

5 What are the challenges of dynamic analysis?

Dynamic analysis poses certain challenges when designing structures for extreme events, such as needing more data and assumptions than static analysis. This includes the characteristics of dynamic loads, the damping and mass distribution of the structure, and nonlinear material models and parameters. Additionally, dynamic analysis requires more computational resources and time than static analysis, especially for nonlinear, time history, or random vibration analysis. Lastly, it requires more expertise and experience than static analysis due to its use of sophisticated methods and software tools, as well as complex results and interpretations.

6 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?